Coating apparatus



Dec. 26, 1939. e. 'r. CHURCH COATING APPARATUS Filed March 29; 1957 2Sheets-Sheet 1 an IN VENT OR. 6507265 7-" CHURCH ATTORNEYS Dec. 26,1939. CHURCH 2,184,610

COATING APPARATUS Filed March 29, 1937 INVENTOR. GEOE'GF 7- cHwE'cHATTORNEYS 2 Sheets-Sheet 2 Patented Dec. 26, 1939 UNITED STATES COATINGAPPARATUS George T. Church, Butler, Pa., assignor to The Fretz-Moon TubeCompany, Inc., Butler, Pa., a corporation of Pennsylvania ApplicationMarch 29,

2 Claims.

This invention relates to the art of applying coating material to pipes,bars and the likepand more particularly to new and improved apparatusfor handling articles during the coating operation.

This invention is particularly adapted to a process of coating pipes andthe like wherein the pipes are coated by immersion in a bath of moltenmetal, for example, galvanizing material.

length of pipe should remain in the bath of coating material for aperiod of time, determined by the thickness of the coating desired andthe type of material used, and that each length of pipe be subjected tothe coating bath for the same length of time. Where such practice is notfollowed the coated articles may have non-uniform coatings, or brittlecoatings which readily flake or peel oif, or the articles may becomewarped or distorted due to being subjected to the coating bath for toogreat a length of time.

Where apparatus made in accordance with the present invention isemployed in coating pipe with molten metal a pipe having a uniform,closely adherent ,coating is produced. Brittle coatings which do notadhere to, or are not alloyed with, the surface of the pipe are avoided,and furthermore the pipes are substantially straight when dischargedfrom the coating bath.

In the drawings-accompanying and forming a part of this specification:

Figure 1 is a top plan view of apparatus-constructed in accordance withthe present inven-,

tion,

Figure 2 is an enlarged transverse sectional view taken on the line 22of Figure 1,

Figure 3 is a sectional view taken on the line 3-3 of Figure 2, I

Figure 4 is an enlarged front view illustrating the timing mechanism foroperating the switch of the reversible motor circuit, and

Figure 5 is a side elevational view of the ep paratus shownin Figure 4.i

In the drawings, Figures 1 to 3,.inclusive, there is illustratedapparatus made in accordance with the present invention including anelongated tank or pot 2 of .suificient size capable of holding aplurality of pipes A and containing the molten metal for coating thepipes. The pipes suitable table 4 positioned along one side of the tank.In moving through the tank 2 the pipes which slope downwardlyfrom theentry side of In such a process, it is highly desirable that each areintroduced laterally into the tank 2 from a' 1937, Serial No. 133,518

the tank to a point below the discharge side of the tank. Each of thesupporting members 6, 6a and 6b is formed with a substantiallyhorizontal portion 8 upon which the pipes rest prior to their removalfrom the tank. The horizontal portion 8 of the supporting member 6 ispreferably disposed at a lower level than the horizontal portions of thesupporting members Ba and 6b to facilitate the up ending of the pipes asthey are being withdrawn from the tank. Vertically disposed above eachof the supporting members 6, 6a and 6b is arranged a guiding device [0,Ilia and Nb, respectively, which cooperates with the inclined surface ofthe supporting members to form a passageway along which the pipes maytravel in the tank. This passageway assures that the pipes will move inthe proper sequence in the tank, and further, that the pipes will bemaintained completely submerged below the surface of the molten metalwhile so disposed in the tank.

. The guiding devices l0, Illa and Illb include a platel2 having a loweredge surface inclined at an angle complemental with the upper inclinedsurface of its associated supporting member. To make the deviceadaptable for coating pipes of different diameters the plate I2 ispreferably mounted for vertical movement so that the passageway may bechanged accordingly.

The guiding devices are supported above the tank 2 on a super-structure,at spaced points therealong. This super-structure consists of spacedlongitudinally extending vertically disposed plates l4 and I6, which arepreferably connected together at their upper ends by a- U- shaped beaml8. The guiding devices are mounted on the upper edge surface of theplates I4 and l6 and each device includes a pair of transverselyextending spaced I-beams 20 which support therebetween a pair of spacedbearing or guiding blocks 22. The bearing blocks 22 are adapted toslidably receive the upper ends of hangers 24, and 24a which are securedto the guide plate l2 as at 26. Forraising and lowering the plate ii!the hangers 24 and 24a have formed 5 thereon racks .28 and 2811,respectively, which -en'- gage with :pinions 3!) and 30d" mounted on'the' blocks 22. The pinions 30 of the spaced guiding devices l0, -l0aand lb are operatively connected together by shafts 32, and the pinions30a are connected by the shafts 32a. Intermediate the pinions 30 and 30aof the guiding device III are a pair of spurgears 34, one of which ismounted on one end'of the shaft 36. The other end of the shaft 3615provided with a hand wheel 38. Rotation of the hand wheel 38 mounted onthe end of the shaft 36 rotates the spur gears 34 which in turn rotatepinions 30 and 30a, whereby raising or lowering of all the plates I2 maybe accomplished, resulting in the passageways between each of thesupporting members 6, 6a and 6b and their complemental guide plates l2being substantially equal. The plate I2 is guided in its verticalmovement between spaced guides 40 secured to one surface of the plate l4and between spaced guides 42 depending from the lower surface of beam[8.

In the coating of pipes where it is desired to obtain a uniform producthaving a closely adherent coating it is highly important that the pipesbe subjected to the coating material for a. predetermined length oftime. To obtain these desired results the pieces of pipe should beintroduced into the tank of molten metal one at a time, should remainimmersed-in the coating material a predetermined period of time andshould be withdrawn from the tank in the same manner in which they wereintroduced. For this purpose, as well as to obtain maximum productionfrom the device, a plurality of reciprocating pusher rods 44, 44a and441) are employed to introduce into and move the pipes through themolten metal in the tank.

The pusher rods 44, 44a and 44b are preferably flanged on their lowersurface and when operatively positioned, straddle and ride upon the'supporting members 6, 6a and 6b, respectively. The pusher rods are madeof different lengths, for example the rod 44a is longer than the rod 44and rod 44b longer than rod 44a so that the pipes will be moved alongthe passageway in an angular position. This permits the molten metal torun freely upwardly through the pipes causing their inner surfaces to bethoroughly coated.

For reciprocating the pusher rods there is secured to the end of eachrod arack 46. which slidably engages in spaced guiding or supportingblocks 48 and 58 integrally formed with a bearing bracket 54 which ismounted on the outwardly extending end of the transverse beams 20. Apinion 55 mounted in bearings 56 and splined to the longitudinallyextending shaft 58 is positioned between each set of guide blocks 48 and58 in engagement with the racks 46. The end of the driving shaft 58 isconnected to a speed reducing unit 601which is operatively connected toa reversible motor 62 through a variable speed changing device 64 whichcontrols the rate of speed of the pusher rods.

The length of the stroke of the pusher arms is controlled by themechanism illustrated in Figures 4 and 5 of the drawings. This mechanismcomprises a gear wheel 66 driven by means of a pinion 68 carried on anextension of the shaft 10 of the speed reducing unit 68. On one face ofthe gear wheel 66 are positioned outwardly extending pins 12 and I4engageable with the end of a rocker arm 16 pivotally mounted on a shaft18 extending outwardly from the panel which carries the reversing switch82 controlling the circuit to the motor 62. The pins 12 and 14 may bepositioned at various positions on the face of type of pipe beingcoated.

. 64 which controls the rate of travel of the pusher rods and themechanism which determines the length of stroke of the rods, it ispossible to fix a definite time period during which each pipe isdisposed within the tank. This period can be readily adjusted to suitthe particular size and In the operation of the device a plurality ofpipes are positioned on the table 4 and an operator rolls them one at atime onto the supporting members 6, 6a and 6b between each stroke of thepusher rods 44, 44a and 44b, the pusher rods being at the end of itsreturn stroke as each pipe is placed on the ends of the supportingmembers. When the pipe is positioned on the upper end of the supportingmembers it is engaged by the end of the pusher rods 44, 44a and 44b andforced under the surface of the molten metal in the tank 2. In view ofthe fact that the pusher rods are of different lengths the pipe isforced into the bath on an angle which permits the molten metal to flowupwardly through the pipe thereby completely coating the inner surfacethereof.

The pipes are moved along the passageway formed between the supportingmembers and the plates I! by the pusher rods and come to rest on thehorizontal portions 8 of the supporting members. By the time the pipeshave reached this position the inner and outer surfaces thereof havebeen completely coated, they are then picked up by an operator and oneend brought into engagement with the magnetic roller 92 which draws thepipe from the tank and passes it on to subsequent manufacturingoperations.

Having thus described the invention what is desired to obtain by LettersPatent is defined in the appended claims.

I claim:

1. Apparatus for coating pipes comprising a tank for molten metal, meansdefining a passage-way along which pipes may travel broadside insequence into the tank, means including reciprocating pusher rods formoving pipes along said passageway, means for positively reciproeatingsaid pusher rods at the same speed in op-.

posite directions, and means for varying the length of travel of saidrods.

2. Apparatus for coating pipes comprising a tank for molten metal, meansdefining a passage-way along which pipes may travel broadside insequence into the tank, means including reciprocating pusher rods formoving pipes along 'said passageway, means for positively reciprocatingsaid pusher rods at the same speed in 0p posite directions, and separatemeans for varying the speed and length of travel of said rods.

GEORGE T. CHURCH.

